• Title/Summary/Keyword: Biophysics

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Transbilayer Effects of n-Alkanols on the Fluidity of Model Membranes of Total Lipids Extracted from Synaptosomal Plasma Membrane Vesicles (n-Alkanols가 소의 대뇌피질 Synaptosomal Plasma Membrane Vesicles로부터 추출 제제한 총지질 인공세포막 이중층간에 형성된 비대칭적 유동성에 미치는 비대칭적 영향)

  • Yun, Il;Kang, Jung-Sook
    • The Korean Journal of Pharmacology
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    • v.28 no.2
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    • pp.191-199
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    • 1992
  • Selective quenching of 1,6-diphenyl-1,3,5-hexatriene (DPH) by trinitrophenyl groups was utilized to examine the transbilayer fluidity asymmetry of model membranes of total lipids (SPMVTL) extracted from synaptosomal plasma membrane vesicles (SPMV). The polarization (P), anisotropy (r), limiting anisotropy $(r_{\infty})$, and order parameter (S) of DPH in the inner monolayer were 0.031, 0.025, 0.033, and 0.070, respectively, greater than calculated for the outer monolayer of SPMVTL. Selective quenching of DPH by trinitrophenyl groups was also utilized to examine the effects of n-alkanols on the individual monolayer structure of SPMVTL. n-Alkanols fluidized the hydrocarbon region of bulk SPMVTL, and the potencies of n-alkanols up to 1-nonanol increased with carbon chain length. It appears that the potencies in bilayer fluidization increase by 1 order of magnitude as the carbon chain length increases by two carbon atoms. The cut-off phenomenon was reached at 1-decanol, where further increase in hydrocarbon length resulted in a decrease in pharmacological activity. The n-alkanols had greater fluidizing effects on the outer monolayer as compared to the inner monolayer of SPMVTL, even though these selective effects tended to become weaker as carbon chain length increased. Thus, it has been proven that n-alkanols exhibit selective rather than nonselective fluidizing effects within transbilayer domains of SPMVTL.

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Effect of Lidocaine-HCl on Microviscosity of Phosphatidylcholine Model Membrane

  • Chung, In-Kyo;Kim, Inn-Se;Choi, Chang-Hwa;Cho, Goon-Jae;Kim, Jin-Bom;Son, Woo-Sung;Jang, Hye-Ock;Yun, Il
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.243-251
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    • 2000
  • In order to provide a basis for studying the molecular mechanism of pharmacological action of local anesthetics and to develop a fluorescence spectroscopic method which can detect the microviscosity of native and model membranes using intramolecular excimerization of 1,3-di(l-pyrenyl)propane (Py-3-Py), we examined the effect of lidocaine HCl on the microviscosity of model membranes of phosphatidylcholine fraction extracted from synaptosomal plasma membrane vesicles (SPMVPC). The excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py in liquid paraffin was a simple linear function of $T/{\eta}.$ Based on this calibration curve, the microviscosity values of the direct probe environment in SPMVPC model membranes ranged from $234.97{\pm}48.85$ cP at $4^{\circ}C$ to %19.21{\pm}1.11$ cP at $45^{\circ}C.$ At $37^{\circ}C,$ a value of $27.25{\pm}0.44$ cP was obtained. The lidocaine HCl decreased the microviscosity of SPMVPC model membranes in a concentration-dependent manner, with a significant decrease in microviscosity value by injecting the local anesthetic even at the concentration of 0.5 mM. These results indicate that the direct environment of Py-3-Py in the SPMVPC model membranes is significantly fluidized by the lidocaine HCl. Also, the present study explicitly shows that an interaction between local anesthetics and membrane lipids is of importance in the molecular mechanism of pharmacological action of lidocaine HCl.

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Effects of Keumsa Sangwhang (Phellinus linteus) Mushroom Extracts on the Natural Killer Cell Activity in Human (금사상황버섯 추출물이 사람의 natural killer 세포 활성에 미치는 영향)

  • Eom, Sang-Yong;Zhang, Yan-Wei;Kim, Nam-Sik;Kang, Jong-Won;Hahn, Youn-Soo;Shin, Kyeong-Seob;Song, Hyung-Gen;Park, Soon-Young;Kim, Jeong-Su;Kim, Heon;Kim, Yong-Dae
    • Korean Journal of Food Science and Technology
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    • v.38 no.5
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    • pp.717-719
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    • 2006
  • A randomized, double blind, placebo-controlled human intervention study involving 62 healthy volunteers was performed to investigate the effects of Keumsa sangwhang (Phellinus linteus) mushroom extracts (KPLE) on natural killer (NK) cell activity in peripheral blood. The volunteers were randomly distributed into two groups, one receiving KPLE (3.3 g/day) and the other a placebo by oral administration for 8 weeks. In this study, the number of NK cells did not increase with KPLE administration, however the cytotoxic activity of NK cells against the Jurkat leukemia cell line increased significantly. This result suggests that administration of KPLE induces cell-mediated immunity by increasing NK cell activity in humans.

Cytokine expression and localization during the development of glomerulosclerosis in FGS mice

  • Park, Sang-Joon;Lee, Sae-Bom;Lee, Young-Ho;Ryu, Si-Yun;Jeong, Kyu-Shik;Lee, Cha-Soo
    • Korean Journal of Veterinary Pathology
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    • v.3 no.1
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    • pp.15-25
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    • 1999
  • To elucidate the mechanism of age-related development in FGS/NgaKIST mice with spontaneous glomerulosclerotic lesion, we examined expression and localization of various cytokine mRNA in the kidney in the progression of diseases. This mouse model is the first to develop spontanously occuring glomerosclerotic lesion in the kidney. In this study, we detected the up-regulation of local cytokine genes such as IL-1$\beta$, IL-2, IL-6, IL-10, TNF-$\alpha$, TGF-$\beta$, and IFN- $\gamma$ in the kidneys. In RT-PCR and Southern blot analysis, we detected gradual expressions of cytokine mRNA of IL-1$\beta$, IL-2, IL-6, IFN- $\gamma$, and TNF $\alpha$ mRNA during the course of disease. Other cytokines including IL -10 and TGF -$\beta$ were found to be appeared the slightly expressed level at 3 to 12 weeks before onset of inflammatory lesion but they are highly expressed at the end-stage of the disease accompaning high proteinurea and wasting. In situ RT-PCR, each cytokine mRNA were specifically localized in a variety of cells including mesangial, endothelial, parietal epithelial, tubular epithelial, arterial muscle cell, and infiltrated inflammatory cells. In addition, TNF - $\alpha$was detected moderately in the visceral and parietal epithelial cell, but weakly in endothelial and mesangial cells, whereas IL-1 $\beta$ and IL -6 were strong in mesangial regions. IL-6 and TNF- $\alpha$ was highly localized in the damaged proximal and collecting tubules. Especially, TGF -$\beta$ mRNA was highly found in mesangial cells within glomerulus and interstitium during the end-stage of this disease.. These results indicate that pro inflammatory cytokines such as IL-1 $\beta$, IL-2, IL-6, and TNF- $\alpha$ were gradually expressed from the early stage of this disease to the end-stage, and that IL-10 and TGF-$\beta$ may be important in the accumulation of extracellular matrix(ECM) within glomerulus and periglomerular fibrosis in the progression of this disease as well as tissue destruction in end-stage of this disease.

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Variation of Meat Quality Parameters Due to Conformation and Fat Class in Limousin Bulls Slaughtered at 25 to 27 Months of Age

  • Guzek, Dominika;Glabska, Dominika;Pogorzelski, Grzegorz;Kozan, Karolina;Pietras, Jacek;Konarska, Malgorzata;Sakowska, Anna;Glabski, Krzysztof;Pogorzelska, Ewelina;Barszczewski, Jerzy;Wierzbicka, Agnieszka
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.5
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    • pp.716-722
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    • 2013
  • The aim of the present study was to determine the influence of age of animal, hot carcass weight, pH, conformation and fat class on basic beef quality attributes (tenderness, sarcomere length, basic chemical composition, marbling and colour) in a group of purebred animals. The object of the study was beef of Limousin bulls (25 to 27 months, hot carcass weight - $432{\pm}31$ kg, "U" conformation class, "2"-"3" fat class). Analysed cuts were Infraspinatus muscle from the blade and Longissimus dorsi muscle from the cube roll and the striploin. Tenderness was analysed with universal testing machine, colour - chromometer analysis, sarcomere length - microscopic method, basic chemical composition - near-infrared spectroscopy and marbling - computer image analysis. No differences in tenderness and sarcomere length were observed within the age groups of Limousin bulls (age of 25, 26, 27 months) (p>0.05). Moisture (p = 0.0123) and fat (p = 0.0250) content were significantly different for meat of animals slaughtered at the age of 25 and 27 months. No influence of pH value on tenderness was observed, but at the same time, influence on sarcomere length (p = 0.039) and $b^*$ component of colour (0.045) was found. For "U" conformation class, in subclasses, as well as for fat classes "2"-"3", there were no differences in tenderness, sarcomere length and colour components. Higher fat content was observed in the higher fat class, rather than in lower, however this feature was not associated with marbling.

Evaluation of Nutrient Intakes in the Hemodialysis Patients According to the Socioeconomic Status - In Daejeon and Chungnam Areas - (혈액투석환자의 사회경제적 수준에 따른 영양소 섭취상태의 평가 - 충남지역을 중심으로 -)

  • Chung, Young-Jin;Park, Yoo-Sin;Kim, Han-Sook;Chang, Yu-Kyung;Kim, Chan
    • Journal of Nutrition and Health
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    • v.35 no.5
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    • pp.544-557
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    • 2002
  • This study was performed to evaluate the quality of nutrient intakes of the hemodialysis patients (26 men and 23 women) according to the socioeconomic status by 3-day dietary recall in Daejeon city and Chungnam area, Korea. Mean age of the subjects was 50.7 yrs and BMI was 22.0 $\pm$ 0.4 kg/$m^2$. Education level was divided into two groups ($\leq$ 9 years: LE group, 9 years: HE group), and monthly family income level was divided into three groups (< 500,000 won: LI group, 500,000-1,499,999 won: MI group, $\geq$ 1,500,000 won : HI group). The data were analyzed by Student t-test and Oneway ANOVA using SPSS 9.0 version at p < 0.05 level. Intakes of energy, carbohydrates, cholesterol, potassium, thiamin and riboflavin were significantly higher in HE group than in LE group (p < 0.05). Intakes of all the nutrients except protein and phosphorus were less than Korean RDA, and INQs (Index of Nutritional Quality) of most nutrients were lower than 1.0 but cholesterol, phosphorus. thiamin and niacin being over 1.0 in HE group. MAR (Mean adequacy ratio) of all the nutrients (e.g., energy, protein, calcium, phosphorus, iron, vitamin A, vitamin C, thiamin, riboflavin and niacin) was significantly higher in HE group (0.61 $\pm$ 0.04) than in LE group (0.48 $\pm$ 0.03) at p = 0.036. Intakes of energy, protein (total, animal and plant), fat, cholesterol, potassium, calcium, phosphorus, iron, vitamin A, thiamin and riboflavin were also significantly higher in HI group than in LI and MI group (p < 0.05). Daily intakes of most nutrients were less than Korean RDA except protein ed phosphorus in HI poop, and INQs of thiamin, niacin and phosphorus were higher than 1.0, while those of calcium, iron, vitamin A and riboflavin were lower than 1.0. MAR of energy and 9 nutrients was significantly higher in HI group (0.70 $\pm$ 0.04) than in LI group (0. 56 0.04) and MI poop (0.47 $\pm$ 0.03) at p = 0.000. In conclusion, quality of nutrient intakes, especially energy and protein, was significantly influenced by socioeconomic status such as education and monthly income (p < 0.05). This result suggests that it would be very helpful to develop nutritional education programs considering hemodialysis patients' education levels, and to improve public supports (e.g., medical insurance system, low-rate lease system of dialysis equipments, etc.) focusing on the patients' family income levels f3r their better nutrition and health.

CO2 and Energy Exchange in a Rice Paddy for the Growing Season of 2002 in Hari, Korea (한국 하리 논에서의 2002년 생장기간의 CO2와 에너지의 교환)

  • Byung-Kwan Moon;Jinkyu Hong;Byoung-Ryol Lee;Jin I. Yun;Eun Woo Park;Joon Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.5 no.2
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    • pp.51-60
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    • 2003
  • Rice, which occupies about 60% of the farmland in Korea, is a staple crop in Asia. It not only absorbs $CO_2$ from the atmosphere, but also emits carbon in a form of CH$_4$. It has a potential role in the global budget of greenhouse gases because of its relative contributions of carbon absorption and emission associated with changing hydrologic cycle. To better understand its current and future role, seasonal variations of energy and $CO_2$ exchange in this critical ecosystem need to be quantified. The purpose of this study was to measure, document and understand the exchange of energy and $CO_2$ in a typical rice paddy in Korea throughout the whole growing season. Since late April of 2002, we have conducted measurements of energy and $CO_2$ exchange in a rural rice paddy at Hari site, one of the Korea regional network of tower flux measurement (KoFlux). After the quality control and gap-filling, the observed fluxes were analyzed in the context of micrometeorology and biophysics. $CO_2$ and energy exchanges varied significantly with land cover changes (e.g., plant growth stages), in addition to changes in weather and climate conditions. This study, reporting first direct measurement of energy and $CO_2$ exchange over a rice paddy in Korea, would serve as a useful database as one of the reference sites in AsiaFlux and FLUXNET.

The Substates with Mutants That Negatively Charged Aspartate in Position 172 Was Replaced with Positive Charge in Murine Inward Rectifier Potassium Channel (Murine Kir2.1)

  • So, I.;Ashmole, I.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.5
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    • pp.267-273
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    • 2003
  • We have investigated the effect on inducing substate(s) of positively charged residues replaced in position 172 of the second transmembrane domain in murine inward rectifier potassium channels, formed by stable or transient transfection of Kir2.1 gene in MEL or CHO cells. Single channel recordings were obtained from either cell-attached patches or inside-out patches excised into solution containing 10 mM EDTA to rule out the effect of $Mg^{2+}$ on the channel gating. The substate(s) could be recorded with all mutants D172H, D172K and D172R. The unitary current-voltage (I-V) relation was not linear with D172H at $pH_i$ 6.3, whereas the unitary I-V relation was linear at $pH_i$ 8.0. The relative occupancy at $S_{LC}$ was increased from 0.018 at $pH_i$ 8.0 to 0.45 at $pH_i$ 5.5. In H-N dimer, that was increased from 0.016 at $pH_i$ 8.0 to 0.23 at $pH_i$ 5.5. The larger the size of the side chain or $pK_a$ with mutants (D172H, D172K and D172R), the more frequent the transitions between the fully open state and substate within an opening. The conductance of the substate also depended upon the pKa or the size of the side chain. The relative occupancy at substate $S_{LC}$ with monomer D172K (0.50) was less than that in K-H dimer (0.83). However, the relative occupancy at substate with D172R (0.79) was similar to that with R-N dimer (0.82). In the contrary to ROMK1, positive charge as well as negative charge in position 172 can induce the substate rather than block the pore in murine Kir2.1. The single channel properties of the mutant, that is, unitary I-V relation, the voltage dependence of the mean open time and relative occupancy of the substates and the increased latency to the first opening, explain the intrinsic gating observed in whole cell recordings.

DNA Binding Studies and Cytotoxicity of the Novel 1,10-phenanthroline Palladium(II) Complexes of Dithiocarbamate Derivatives (디티오카르바메이트 유도체의 새로운 1,10-페난트롤린 팔라디움(II) 착물의 DNA 결합 성질 및 세포독성에 관한 연구)

  • Mansouri-Torshizi, Hassan;Saeidifar, Maryam;Ghasemi, Zahra Yekke;Khastan, Mahmood;Divsalar, Adeleh;Saboury, Ali Akbar
    • Journal of the Korean Chemical Society
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    • v.55 no.1
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    • pp.70-80
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    • 2011
  • Two new palladium (II) complexes, [Pd (phen)(pip-dtc)]$NO_3$ and [Pd(phen)(mor-dtc)]$NO_3$, (where phen is 1,10-Phenantroline, pip-dtc is piperidinedithiocarbamate anion and mor-dtc is morpholinedithiocarbamate anion) have been synthesized and characterized by elemental analysis, spectroscopic studies (FT-IR, $^1H$ NMR, UV-Vis) and conductance measurement. In these complexes, the dithiocarbamate ligands coordinate with Pd (II) center as bidentate with two sulfur atoms. These two complexes have been tested against chronic myelogenous leukemia cell line, K562. They show $IC_{50}$ values less than cisplatin and thus the mode of binding of the complexes to calf thymus DNA (CT-DNA) were investigated by ultraviolet difference and fluorescence spectroscopy. They can denature DNA, exhibit cooperative binding and intercalate into DNA. Several binding and thermodynamic parameters are also described.

A Role for Ginseng in the Control of Postprandial Glycemia and Type 2 Diabetes

  • Vuksan Vladimir;Sievenpiper John L;Xu Zheng;Zdravkovic Uljana Beljan;Jenkins Alexandra L;Arnason John T;Bateman Ryon M.;Leiter Lawrence A;Josse Robert G;Francis Thomas;Stavro Mark P
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.1-19
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    • 2002
  • The use of herbals has increased considerably while their efficacy and safety remain untested. This unsupported surge in demand has prompted a call for their clinical evaluation. One area in which evaluations are emerging is ginseng and diabetes. Growing evidence is accumulating from in vitro and animal models indicating that various ginseng species, American (Panax quinquefolius L), Asian (Panax ginseng C.A. Meyer), Korean Red, San-chi (Panax notoginseng [Burk.] P.R. Chen), and the non-panax species Siberian (Eleutherococcus senticossus) ginsing, and their fractions, saponins (ginsenosides) and peptidoglycans (panaxans for panax species and eleutehrans for Siberian ginseng), might affect carbohydrate metabolism and related signaling molecules. Recent human studies from our laboratory have also shown a blood glucose lowering effect of American ginseng (AG) and some other ginseng spices postprandially after acute administration and chronically after administration for 8-weeks in people with type 2 diabetes. Although generally encouraging, these data only indicate a need for more evaluations of ginsengs safety and efficacy. Because of poor industry standardization, it is not known whether all ginsengs will affect blood glucose. In this regards some ginseng batches have demonstrated null effects while others have even raised postprandial glycemia. Clinical research should therefore focus on components involved in its glucose lowering effects.

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